1. Field of the Invention
The present invention relates to a sheet processing apparatus for discriminating a plurality of sheets, classifying them into categories such as kind, front and back, top and bottom, and staining state, and stacking the classified sheets respectively in a predetermined number.
2. Description of the Related Art
Conventionally, as a sheet processing apparatus, a banknote processing apparatus for inserting a plurality of banknotes into the receiving portion, taking out the inserted banknotes from the take-out portion onto the conveying path one by one, discriminating the banknotes conveyed on the conveying path by the detector, stacking regular bills discriminated as reusable banknotes by the detector in the stacker, moving-a predetermined number (for example, 100) of regular bills from the stacker to the banding unit, and banding them is known.
Among this kind of banknote processing apparatuses, for example, a type of apparatus having only one set of stacker and banding unit, at the point of time when the 100th regular bill judged as reusable by the detector passes the detector, stops the banknote take-out operation by the take-out portion once. And, the apparatus moves the 100 regular bills stacked in the stacker to the banding unit and bands them with a paper band. Furthermore, after moving the 100 regular bills from the stacker to the banding unit, the apparatus restarts the banknote take-out operation by the take-out portion.
At this time, regular bills after the 100th bill taken out on the conveying path from the take-out portion to the detector at the point of time when the banknote take-out operation is stopped are ejected into the reject box without being stacked in the stacker. And, after all the banknotes are taken out, the rejected regular bills are inserted into the receiving portion again by the hand operation of an operator. In this case, the operation of reinsertion of the rejected regular bills into the receiving portion by the hand operation requires a great deal of time and is troublesome.
Therefore, as indicated in U.S. patent application Ser. No. 09/978,670, there is such a type of apparatus available as to install 2 sets of stackers for stacking regular bills and banding units for banding stacked regular bills and to alternately stack and band 100 regular bills. However, also in this type of apparatus, when the stacker (or banding unit) of one set is broken down or the paper bands of the banding unit of one set are all gone, only the stacker and banding unit of one set can be used and the same problem as the aforementioned arises.